Hey Ken, It's not really all that common in saltwater setup. My local public aquarium (Vancouver Aquarium) uses it on tanks with large bio loads to keep the waist nutrients in check. I don't really think you will need one if you use good maintenace (water changes and gravel cleaning), have good filtration (wet dry filter) and quarantine all new arrivals. Check out this place. http://www.aquaticeco.com/aquatic1v1/index.icl?orderidentifier=ID1052177769461493A19 They are quite helpful with answering questions about equipment. Cheers, Victor Eng ----------------------------------------------------------------------- -- This is the apistogramma mailing list, apisto@listbox.com. For instructions on how to subscribe or unsubscribe or get help, email apisto-request@listbox.com. apisto-digest@listbox.com also available. Web archives at http://lists.thekrib.com/apisto Trading at http://blox.dropship.org/mailman/listinfo/apisto_trader